1. Field of the Invention
The present invention generally relates to an intrauterine device (IUD) and to an inserter for placing the same. More specifically the invention relates to a combination of a one-hand-held inserter for positioning a T-shaped intrauterine device and to a T-shaped intrauterine device that are designed to make insertion easier while minimizing patient's discomfort and pain.
2. Discussion of the Related Art
Intrauterine devices and inserters for the same are well known. An intrauterine device (IUD) is a reversible, long acting, contraceptive device that is placed inside the uterus and can remain there for a few years. At any time that the woman plans to have a child, it can be easily removed by a clinician. Many women find the IUD to be very convenient because unlike oral contraceptives which require daily attention, an intrauterine device requires little action once it is in place.
Over the years various types of intrauterine devices have been proposed and applied. At present there are two types of IUDs in use: a copper-based IUD and a hormonal IUD. Copper-based IUDs are available in the T-framed shape or as frameless IUDs. The T-shaped IUDs comprise a T-shaped plastic frame having an elongated body partly wrapped by a copper coil and a pair of flexible transverse arms that hold the IUD in place near the top of the uterus. The IUD is inserted into the uterus with the transverse arms folded to facilitate the insertion through the cervical canal. Once the device is positioned inside the uterus, the arms are released and assume their transverse orientation. Depending on the particular device, the arms are either folded backward against the stem, as for example in TC-380A. (e.g., ParaGard®), or are folded in the forward direction against each other as in Nova-T type IUDs. The frameless copper IUD (e.g., GyneFix®) does not contain a T-shape frame but is a loop that holds several copper tubes and is anchored into the uterus fundus by a suture.
Of particular interest of the present invention are hormonal IUDs (also known as intrauterine system—IUS) which contain reservoir of hormone that is gradually released into the uterine cavity. At present there is only one hormonal IUD available for use, the T-frame LNG-20 distributed by Schering Og under the name Mirena®. It consists of a flexible plastic T-shaped frame surrounded by a hormone (levonorgestrel) cylinder. Hormonal IUDs have other benefits besides being contraceptive and may also be given for treatment of hormonal disorders and for hormone replacement therapy. Compared to copper-based IUDs such as for example the Nova-T, the LNG-20 is bulkier, having a body of larger diameter. Its insertion procedure requires more expertise and may be associated with more discomfort and pain to the patient.
The insertion and removal of an IUD is a medical procedure performed by a physician. The IUD is inserted through the cervix and into the uterine cavity by means of an inserter that typically includes an insertion tube that accommodates the IUD and a plunger. For T-shaped IUD the lateral arms are folded prior to insertion. An IUD typically also includes a string extending from its bottom end, which serves for monitoring the IUD and for facilitating its removal.
IUD is one of the most effective reversible contraceptive methods and has certain advantages over other birth control means with respect to cost-effectiveness and convenience, and because it is a long-term, reversible method, it can meet the needs of many women. However, despite these advantages, IUDs are widely used only in a few large countries, such as China, Egypt, and Vietnam, and are little used in most countries. In the United States, for example, only about 2% of women who use birth control means, use IUDs.
One of the reasons for IUDs not being more popular is the fear of the discomfort and pain associated with the insertion procedure. In addition, the general practice to perform insertion during the menstrual period may add to the discomfort felt by potential users. Further, although there is no minimum age for using IUD, it is often believed that IUDs should not be given to young women or to women who have never been pregnant.
There is therefore a continuous need to improve intrauterine devices and insertion procedure that may lead to greater acceptability and use of IUDs.
Accordingly, it is the general object of the invention to simplify IUD insertion procedure and to minimize the patient's discomfort and risk of complications during and after insertion.
In particular, it is an object of the present invention to provide an inserter for an intrauterine device that is easier to manipulate, that will make insertion procedure easier to the physician and less painful to the patient and that is simple to manufacture and to use.
It is another object of the present invention to provide an intrauterine device that is easier to insert and remove, that has a simple structure and is easy and inexpensive to manufacture.